Immunodeficiency-Related Lymphoproliferative Disorders

Abstract Lymphoproliferative disorders are innately disorders of the immune system, and the immunodeficiency-related lymphoproliferative disorders are of particular interest because they offer a paradigm for studying the relationships between the immune system and the evolution of neoplastic disease. Immunodeficiency lymphoid disorders are generally classified according to the setting in which they arise, notably posttransplantation, in association with human immunodeficiency virus (HIV) infection, iatrogenic immunodeficiency, and primary immune disorders. Although the various entities offer a complicated spectrum of lymphoid proliferations with heterogeneous morphologies, there are similarities across varying immunodeficiency backgrounds, and a similar spectrum of lymphoproliferative disorders may occur within all categories of immune deficiency. Features held in common include the tendency to involve extranodal sites and to be infected with oncogenic viruses, particularly the Epstein-Barr virus (EBV) and the Kaposi sarcoma–associated herpesvirus, HHV8.